Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 11/9/1999
Publication Date: N/A
Technical Abstract: Colostrum-deprived neonatal piglets are a useful model for research on the systemic manifestations of Escherichia coli O157:H7 infection. Our objective was to determine if colostrum-fed (suckling) neonatal piglets can also be used as such a model. Thirty piglets were allowed to suckle colostrum (< or equal to 8 h) before they were inoculated via gavage with 10**10 CFU of Shiga toxin-producing E. coli O157:H7 (strain 86-24). All piglets developed moderate-to-severe central nervous signs within 24 hours PI and died or were euthanized for humane reasons by 36 h PI. Shivering and tremors rapidly progressed to hind leg weakness, lateral or sternal recumbency and seizures. All piglets had varying degrees of generalized subcutaneous edema. Acute focal central nervous system hemorrhages were seen predominantly in the cerebellum, but also in the medulla oblongata or spinal cord. A severe microscopic angiopathy, characterized by endothelial swelling, severe plasma diapedesis, and focal malacia or multifocal necrosis in the granular layer of the cerebellum, was present in all brain tissues examined. Only two piglets developed diarrhea, but all had attaching and effacing lesions in the large intestine. In contrast, none of 8 piglets inoculated with Shiga toxin-negative E. coli O157:H7 (strain 87-23) developed neurological signs or lesions by 3 days. Strain 87-23 did not cause diarrhea in any of the piglets, but did produce attaching and effacing intestinal lesions in all 8 piglets. The suckling piglet model will be useful for studying systemic disease caused by Shiga toxin-producing E. coli.